Valtteri Bottas set the pace on the final morning of testing at the Red Bull Ring as the teams set about making up for lost time in the dry after Tuesday's rain delay.
The Finn went top in the early moments of the session and continually lowered his benchmark, ending on a 1:10.029 in the Williams FW37. It shaved nearly a second off the best time set in the mixed conditions on Tuesday by Mercedes' Pascal Wehrlein.
Wehrlein was testing for the second day in a row but had switched to the VJM08, which was running with partial upgrades ahead of the launch of its B-Spec car in Silverstone. Of note was a striking new nose design and the team will be boosted by finishing the final morning second behind Williams.
Nico Rosberg got back into the cockpit of the W05 after his victory on Sunday and turned in 34 laps, finishing in third as the only other man to dip inside the 1:10s. Fernando Alonso finished the morning fourth for McLaren but only clocked up 17 laps, by far the lowest mileage count of any other team. The Spaniard finished over a second down on Bottas with a best time of 1:11.178.
Felipe Nasr put Sauber in fifth with a 1:11.228, his best after 44 laps, while GP2 champion Jolyon Palmer continued for Lotus and completed 42 laps of his own. Esteban Gutierrez made a slow start to the session in the Ferrari which Antonio Fuoco damaged on Tuesday, which would account to the Mexican only accumulating 27 laps.
The two Renault-powered teams were the busiest but also the slowest on the timesheets, though as ever it is important not to read too much into headline times during testing. Daniel Ricciardo accumulated a morning's-best 75 laps for Red Bull, while Marco Wittmann finished at the bottom of the leaderboard on his first morning in a Formula One car having racked up 71 laps for Toro Rosso.